jasa pasang lampu taman, instalasi lampu taman

saco-indonesia.com, Gunung Kelud yang berada di perbatasan Kabupaten Blitar dan Kediri, Jawa Timur, berstatus Waspada sejak 2 Februari 2014. Aktivitas vulkanik gunung tersebut telah terpantau terus meningkat.

Catatan Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG) pada Kamis pukul 00.00 WIB hingga 12.00 WIB, telah terjadi dua kali gempa vulkanik dalam dan 21 kali gempa vulkanik dangkal.

Sedangkan total dari 1-6 Februari pukul 12.00 siang WIB, di Gunung Kelud telah terjadi 93 kali gempa vulkanik dalam dan 321 kali gempa vulkanik dalam.

“Dari hari ke hari aktivitas vulkanik di Gunung Kelud meningkat terus,” terang Kepala Bidang Mitigasi Bencana, Gempa Bumi, dan Gerakan Tanah PVMBG (PVMBG), Gede Suantika, di Bandung, Kamis 6 Februari 2014 kemarin.

Bila dibandingkan Januari, lanjut Suantika, kegempaan di Gunung Kelud selama Februari lebih tinggi. Minggu pertama Januari telah tercatat sekali gempa vulkanik dalam dan 18 kali gempa vulkanik dangkal. Minggu kedua Januari telah tercatat empat kali gempa vulkanik dalam dan 10 kali gempa vulkanik dangkal. Minggu ketiga Januari telah terjadi 98 kali gempa vulkanik dalam dan 34 gempa vulkanik dangkal. Minggu keempat Januari telah tercatat ada 79 gempa vulkanik dalam dan 234 gempa vulkanik dangkal.

Suhu air kawah juga terus meningkat dari waktu ke waktu. Hingga tadi siang tercatat suhunya telah mencapai 57 derajat Celcius. Jika aktivitas vulkanik terus meningkat dalam beberapa hari ke depan, ada dampak negatif yang kemungkinan akan terjadi.

"(Kemungkinan) meletus ini,” ungkapnya.

Sementara itu, meski Gunung Kelud akan berpotensi meletus, PVMBG belum meningkatkan status dari Waspada (level II) ke Siaga (level III). Rekomendasi steril pun juga belum diubah.

“Rekomendasi juga masih tetap dua kilometer dari pusat kawah,” pungkasnya.


Editor : Dian sukmawati

GUNUNG KELUD BERPOTENSI MELETUS

Though Robin and Joan Rolfs owned two rare talking dolls manufactured by Thomas Edison’s phonograph company in 1890, they did not dare play the wax cylinder records tucked inside each one.

The Rolfses, longtime collectors of Edison phonographs, knew that if they turned the cranks on the dolls’ backs, the steel phonograph needle might damage or destroy the grooves of the hollow, ring-shaped cylinder. And so for years, the dolls sat side by side inside a display cabinet, bearers of a message from the dawn of sound recording that nobody could hear.

In 1890, Edison’s dolls were a flop; production lasted only six weeks. Children found them difficult to operate and more scary than cuddly. The recordings inside, which featured snippets of nursery rhymes, wore out quickly.

Yet sound historians say the cylinders were the first entertainment records ever made, and the young girls hired to recite the rhymes were the world’s first recording artists.

Year after year, the Rolfses asked experts if there might be a safe way to play the recordings. Then a government laboratory developed a method to play fragile records without touching them.

Audio

The technique relies on a microscope to create images of the grooves in exquisite detail. A computer approximates — with great accuracy — the sounds that would have been created by a needle moving through those grooves.

In 2014, the technology was made available for the first time outside the laboratory.

“The fear all along is that we don’t want to damage these records. We don’t want to put a stylus on them,” said Jerry Fabris, the curator of the Thomas Edison Historical Park in West Orange, N.J. “Now we have the technology to play them safely.”

Last month, the Historical Park posted online three never-before-heard Edison doll recordings, including the two from the Rolfses’ collection. “There are probably more out there, and we’re hoping people will now get them digitized,” Mr. Fabris said.

The technology, which is known as Irene (Image, Reconstruct, Erase Noise, Etc.), was developed by the particle physicist Carl Haber and the engineer Earl Cornell at Lawrence Berkeley. Irene extracts sound from cylinder and disk records. It can also reconstruct audio from recordings so badly damaged they were deemed unplayable.

“We are now hearing sounds from history that I did not expect to hear in my lifetime,” Mr. Fabris said.

The Rolfses said they were not sure what to expect in August when they carefully packed their two Edison doll cylinders, still attached to their motors, and drove from their home in Hortonville, Wis., to the National Document Conservation Center in Andover, Mass. The center had recently acquired Irene technology.

Audio

Cylinders carry sound in a spiral groove cut by a phonograph recording needle that vibrates up and down, creating a surface made of tiny hills and valleys. In the Irene set-up, a microscope perched above the shaft takes thousands of high-resolution images of small sections of the grooves.

Stitched together, the images provide a topographic map of the cylinder’s surface, charting changes in depth as small as one five-hundredth the thickness of a human hair. Pitch, volume and timbre are all encoded in the hills and valleys and the speed at which the record is played.

At the conservation center, the preservation specialist Mason Vander Lugt attached one of the cylinders to the end of a rotating shaft. Huddled around a computer screen, the Rolfses first saw the wiggly waveform generated by Irene. Then came the digital audio. The words were at first indistinct, but as Mr. Lugt filtered out more of the noise, the rhyme became clearer.

“That was the Eureka moment,” Mr. Rolfs said.

In 1890, a girl in Edison’s laboratory had recited:

There was a little girl,

And she had a little curl

Audio

Right in the middle of her forehead.

When she was good,

She was very, very good.

But when she was bad, she was horrid.

Recently, the conservation center turned up another surprise.

In 2010, the Woody Guthrie Foundation received 18 oversize phonograph disks from an anonymous donor. No one knew if any of the dirt-stained recordings featured Guthrie, but Tiffany Colannino, then the foundation’s archivist, had stored them unplayed until she heard about Irene.

Last fall, the center extracted audio from one of the records, labeled “Jam Session 9” and emailed the digital file to Ms. Colannino.

“I was just sitting in my dining room, and the next thing I know, I’m hearing Woody,” she said. In between solo performances of “Ladies Auxiliary,” “Jesus Christ,” and “Dead or Alive,” Guthrie tells jokes, offers some back story, and makes the audience laugh. “It is quintessential Guthrie,” Ms. Colannino said.

The Rolfses’ dolls are back in the display cabinet in Wisconsin. But with audio stored on several computers, they now have a permanent voice.

Ghostly Voices From Thomas Edisonís Dolls Can Now Be Heard

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